My iPhone is showing my incorrect location

The navigation function is highly dependent on having a stable connection and good reception service.

1. Make sure there are no obstructions around to interfere with signals and connections, and that your network connection is stable.
2. Navigate to Settings → Privacy → Location Services.
3. Turn location service on.
4. If the location service is already enabled, turn it off and wait for about 20 seconds or several minutes and then turn it back on.
5. If the problem still persists, maybe restarting the iPhone will help?

Would this be a network connection to some remote service (mis)reporting your location for, say, a two-factor login?

Or is this Find My, Apple Maps, or some local app you’re using that’s (mis)reporting an unexpected location?

The former is usually based on the geolocation provided by your ISP, and that can be off by hundreds of kilometers or more.

The latter using location services as mentioned above, and that’s dependent on radio positioning data, and GPS or Galileo or such positioning signals can be unavailable or jammed, and cellular tower based positioning can sometimes be off by several kilometers.